Opportunities for web-based indicators in environmental sciences

This paper proposes a set of web-based indicators for quantifying and ranking the relevance of terms related to key-issues in Ecology and Sustainability Science. Search engines that operate in different contexts (e.g. global, social, scientific) are considered as web information carriers (WICs) and are able to analyse; (i) relevance on different levels: global web, individual/personal sphere, on-line news, and culture/science; (ii) time trends of relevance; (iii) relevance of keywords for environmental governance. For the purposes of this study, several indicators and specific indices (relational indices and dynamic indices) were applied to a test-set of 24 keywords. Outputs consistently show that traditional study topics in environmental sciences such as water and air have remained the most quantitatively relevant keywords, while interest in systemic issues (i.e. ecosystem and landscape) has grown over the last 20 years. Nowadays, the relevance of new concepts such as resilience and ecosystem services is increasing, but the actual ability of these concepts to influence environmental governance needs to be further studied and understood. The proposed approach, which is based on intuitive and easily replicable procedures, can support the decision-making processes related to environmental governance.     

Lateral root formation in the strawberry Fragaria × ananassa Duch. revealed by histone H4 in situ hybridisation

Abstract

Our study was carried out in bench rhizotrons using the Camarosa variety of strawberry (Fragaria × ananassa Duch.), by exciding the apex of fast-growing primary roots at two distances (1 or 8 cm) from the apex. It was demonstrated that new lateral meristems were rapidly induced by excision of the root apex at either distance; after 24 h, histone H4 in situ hybridisation detected groups of cell-organising root primordia just a few millimetres below the cut. After a further 24 h, new lateral roots were about to protrude from the original root. Results show that lateral roots can be formed anywhere along the primary roots of strawberry plants from a few stem cells distributed along the pericycle close to the protoxylem arches.     

The Repeatability Assessment of Three-Dimensional Capsule-Intraocular Lens Complex Measurements by Means of High-Speed Swept-Source Optical Coherence Tomography

Purpose

To rebuild the three-dimensional (3-D) model of the anterior segment by high-speed swept-source optical coherence tomography (SSOCT) and evaluate the repeatability of measurement for the parameters of capsule-intraocular lens (C-IOL) complex.

Methods

Twenty-two pseudophakic eyes from 22 patients were enrolled. Three continuous SSOCT measurements were performed in all eyes and the tomograms obtained were used for 3-D reconstruction. The output data were used to evaluate the measurement repeatability. The parameters included postoperative aqueous depth (PAD), the area and diameter of the anterior capsule opening (Area and D), IOL tilt (IOL-T), horizontal, vertical, and space decentration of the IOL, anterior capsule opening, and IOL-anterior capsule opening.

Results

PAD, IOL-T, Area, D, and all decentration measurements showed high repeatability. Repeated measure analysis showed there was no statistically significant difference among the three continuous measurements (all P > .05). Pearson correlation analysis showed high correlation between each pair of them (all r >0.90, P<0.001). ICCs were all more than 0.9 for all parameters. The 95% LoAs of all parameters were narrow for comparison of three measurements, which showed high repeatability for three measurements.

Conclusion

SSOCT is available to be a new method for the 3-D measurement of C-IOL complex after cataract surgery. This method presented high repeatability in measuring the parameters of the C-IOL complex.     

Synthesis of N1-arylidene-N2-quinolyl- and N2-acrydinylhydrazones as potent antimalarial agents active against CQ-resistant P. falciparum strains

A series of N1-arylidene-N2-quinolyl- and N2-acrydinylhydrazones were synthesized and tested for their antimalarial properties. These compounds showed remarkable anti-plasmodial activity in vitro especially against chloroquine-resistant strains. Their potent biological activity makes them promising lead structures for the development of new antimalarial drugs.     

Novel and potent tacrine-related hetero- and homobivalent ligands for acetylcholinesterase and butyrylcholinesterase.

Based upon synthetic and biochemical results, a novel and potent tacrine analogue and heterobivalent analogues of tacrine, were designed. The role played by the amino groups of homo- and heterobivalent ligands in the interaction with the peripheral and catalytic sites of AChE and BuChE were investigated. The syntheses of these materials together with the results of AChE/BuChE inhibition assays are detailed.     

Home-range characteristics and the influence of seasonality on female reproduction in white-handed gibbons (Hylobates lar) at Khao Yai National Park, Thailand

A three-year (2001-2003) study was carried out on the home range characteristics of seven wild white-handed gibbon (Hylobates lar) groups focusing on the spatio-temporal distribution of food resources at Khao Yai National Park in northeastern Thailand. These results were combined with 23 years (1980-2003) of reproductive performance data on seven females from the same focal groups. Reproductive performance was equal among females with regard to birth, weaning and maturation ratios, and independent of variation in food availability. Offspring mortality, however, was significantly positively correlated with home-range size. In addition, there was an increase in offspring mortality just after weaning, suggesting that the increase in the daily distance traveled by juveniles contributed to this mortality. Conceptions clustered during the first half of the year when food production was at its peak, which presumably allowed females to accumulate sufficient body reserves to resume ovarian cycling. Our results place Khao Yai gibbons closer to Cercopithecidae than great apes in terms of the temporal pattern of reproductive events, though gestation, lactation, inter-birth interval, and offspring maturation are considerably longer in gibbons, placing them closer to the other apes. Our findings underline the unique phylogenetic position of these small-bodied apes in terms of reproductive patterns in primates.     

Strawberry plant relationship through the stolon

Stolon is an elongated, two-node, vegetative, axillary shoot, which supports the ramet (rooted rosette) until it is completely independent on its own roots. The reciprocal capacity of the ramets, in a single runner chain, to sustain the growth and share locally abundant resources or to tolerate a local stress, is still in debate. This capacity may play an important role for improving nursery plant production and for better understanding the natural clonal multiplication. To describe strawberry stolon action, in plant-to-plant relationship, bare-rooted Camarosa ramets, joint in couples by their own stolons (generally, second and third ramet in a runner chain) were transplanted in two pots. The couples of ramets were treated in a factorial experiment with decortication (peeling a 2-mm ring of bark from the stolon), removal of root system or glyphosate application to one of the two ramets. In the studied system, the older ramet was referred as mother and the other as daughter. The two ramets were very similar in age and seem to act with a very limited hierarchic prevalence of the mother. When the root system of one ramet was eliminated, leaf number and chlorophyll content had a very slight decrease, independently in the mother ramet or in the daughter. The decortication did not reduce water integration, in any group of plants, but limited assimilate allocation towards the daughter ramet when the mother ramet had a severe root cut (not vice versa). The glyphosate action resulted localized in the sprayed ramet, which reduced chlorophyll content within 2 days and expired after 4 days.     

Pigeon homing along highways and exits

BACKGROUND: Anecdotal observations and early airplane and helicopter tracking studies suggest that pigeons sometimes follow large roads and use landmarks as turning points during their homeward journey. However, technical limitations in tracking pigeon routes have prevented proof. RESULTS: Here, we present experimental and statistical evidence for this strategy from the analysis of 216 GPS-recorded pigeon tracks over distances up to 50 km. Experienced pigeons released from familiar sites during 3 years around Rome, Italy, were significantly attracted to highways and a railway track running toward home, in many cases without anything forcing them to follow such guide-rails. Birds often broke off from the highways when these veered away from home, but many continued their flight along the highway until a major junction, even when the detour added substantially to their journey. The degree of road following increased with repeated releases but not flight length. Significant road following (in 40%-50% of the tracks) was mainly observed from release sites along northwest-southeast axis. CONCLUSIONS: Our data demonstrate the existence of a learned road-following homing strategy of pigeons and the use of particular topographical points for final navigation to the loft. Apparently, the better-directed early stages of the flight compensated the added final detour. During early and middle stages of the flight, following large and distinct roads is likely to reflect stabilization of a compass course rather than the presence of a mental roadmap. A cognitive (roadmap) component manifested by repeated crossing of preferred topographical points, including highway exits, is more likely when pigeons approach the loft area. However, it might only be expected in pigeons raised in an area characterized by navigationally relevant highway systems.     

Cellular responses to H(2)O(2) and bleomycin-induced oxidative stress in L6C5 rat myoblasts

In muscle cells, reactive oxygen species (ROS) are continually generated. It is believed that these molecules have a well-established role as physiological modulators of skeletal muscle functions, ranging from development to metabolism and from blood flow to contractile functions. Moreover, ROS may contribute to the development of muscle fatigue, inflammation, and degeneration, and may be implicated in many muscle diseases. The aim of the present study was to verify the role of short or prolonged exposure to oxidative stress, generated by different concentrations of H(2)O(2), on growth, chromosomal aberrations, and apoptosis induced in cultured L6C5 rat muscle cells used as model for myoblasts. Our results indicate that, in L6C5 cells, reactive oxygen intermediates (ROI) can activate distinct cell pathways leading to cell growth induction and development of resistant phenotype, or to chromosomal aberrations, cell cycle arrest, or cell death. The positive vs. negative effects of H(2)O(2)-altered redox potential in myoblasts are strictly related to the intensity of oxidative stress, likely depending on the types and number of cellular targets involved. Among these, DNA molecules appear to be very sensitive to breakage by H(2)O(2), although DNA damage is not directly responsible for ROI-induced apoptosis in L6C5 rat myoblasts.     

Analysis of trapped mosquito excreta as a noninvasive method to reveal biodiversity and arbovirus circulation

Emerging and endemic mosquito-borne viruses can be difficult to detect and monitor because they often cause asymptomatic infections in human or vertebrate animals or cause nonspecific febrile illness with a short recovery waiting period. Some of these pathogens circulate into complex cryptic cycles involving several animal species as reservoir or amplifying hosts. Detection of cases in vertebrate hosts can be complemented by entomological surveillance, but this method is not adapted to low infection rates in mosquito populations that typically occur in low or nonendemic areas. We identified West Nile virus circulation in Camargue, a wetland area in South of France, using a cost-effective xenomonitoring method based on the molecular detection of virus in excreta from trapped mosquitoes. We also succeeded at identifying the mosquito species community on several sampling sites, together with the vertebrate hosts on which they fed prior to being captured using amplicon-based metabarcoding on mosquito excreta without processing any mosquitoes. Mosquito excreta-based virus surveillance can complement standard surveillance methods because it is cost-effective and does not require personnel with a strong background in entomology. This strategy can also be used to noninvasively explore the ecological network underlying arbovirus circulation.